Grails Service for GridFS access

gistfile1.groovy

package net.saberco

//Reworked by Andy Kallenbach, SaberCo.net, September 17, 2011
//Refactored saveFile
//Fixed saving extra data fields along with file
//Need to finish an updateFile to overwrite an existing file

import com.mongodb.gridfs.GridFS
import eu.medsea.mimeutil.detector.MagicMimeMimeDetector
import org.springframework.web.multipart.commons.CommonsMultipartFile
import com.mongodb.gridfs.GridFSInputFile
import com.mongodb.DBObject
import com.mongodb.gridfs.GridFSDBFile
import org.bson.types.ObjectId
import com.mongodb.WriteConcern
import javax.servlet.http.HttpServletResponse
import org.apache.commons.io.IOUtils
import org.codehaus.groovy.grails.commons.ApplicationHolder
import com.mongodb.DB
import com.mongodb.BasicDBObject
import com.mongodb.gridfs.GridFSFile

class FilestorageService {

    static transactional = false
	
	def mongo
	def grailsApplication
	
	private HashMap<String, GridFS> _gridfs = new HashMap<String, GridFS>()
	
	public GridFSFile saveFile(String bucket, CommonsMultipartFile file, String filename = null, Map metaData = null) {

		// get content type
		byte[] b = new byte[4096]
		BufferedInputStream s = new BufferedInputStream(file.getInputStream(), 6144)
		s.mark(0)
		s.read(b, 0, 4096)
		s.reset()
		def contentType = getMimeType(b)
	
		saveFile(bucket, s, filename, Map);
	  }
	
	public GridFSFile saveFile(String bucket, File file, String filename, Map metaData = null) {
		saveFile(bucket, file.newInputStream(), getMimeType(file), filename, Map);
	  }
	
	public GridFSFile saveFile(String bucket, byte[] fileContents, String filename, Map metaData = null) {
		saveFile(bucket, new ByteArrayInputStream(fileContents), getMimeType(fileContents), filename, Map);
	 }
		
	public GridFSFile saveFile(String bucket, InputStream fileStream, String ContentType, String filename, Map metaData = null)
	{
		GridFS gfs = getGridfs(bucket);
		
		GridFSInputFile gInputFile = gfs.createFile(fileStream);
		gInputFile.setFilename(filename);
		gInputFile.setContentType(ContentType);
		metaData.each {
			gInputFile.put(it.key.toString(), it.value)
		}
		/*if (metaData) {
		  DBObject mD = gInputFile.getMetaData();
		  metaData.each { 
			  println "key: " + it.key.toString() + " value: " + it.value;
			  mD.put(it.key.toString(), it.value) 
		  }
		}*/
	
		_saveFile(gfs, bucket, gInputFile)
	}
    private GridFSFile _saveFile(GridFS gfs, String bucket, GridFSInputFile gInputFile) {
		String errormsg;
		
		try 
		{
			gInputFile.save();
    	} 
		catch(Exception e) 
		{
			log.error('could not save file ' + gInputFile + ': ' + e.message)
    	}

    	return gInputFile
	}
	
	def GridFSDBFile getFile(String bucket, String id, boolean asObjectId = true) {
		GridFS gfs = getGridfs(bucket);
	
		if (asObjectId) {
		  return gfs.findOne(new ObjectId(id))
		} else {
		  return gfs.findOne(new BasicDBObject('_id', id))
		}
	  }
	
	def GridFSDBFile findFile(String bucket, Map query) {
		GridFS gfs = getGridfs(bucket);
		
		BasicDBObject mongoQuery = new BasicDBObject();
		query.each {
			mongoQuery.put(it.key.toString(), it.value)
		}
		
		GridFSDBFile aFile = gfs.findOne(mongoQuery);
	
		return aFile
	  }
	
	def List find(String bucket, Map query, Integer resultsToSkip, Integer pageSize) {
		GridFS gfs = getGridfs(bucket);
		
		BasicDBObject mongoQuery = new BasicDBObject();
		query.each {
			mongoQuery.put(it.key.toString(), it.value)
		}
		
		return gfs.find(mongoQuery);
	}
	
	def deleteFile(String bucket, Map query) {
		GridFS gfs = getGridfs(bucket);
	
		gfs.remove(query as BasicDBObject)
	  }
	
	private GridFS getGridfs(String bucket) {
		
		def gridfs = _gridfs[bucket]
		if (!gridfs) {			
			def mongoConfig = grailsApplication.config?.grails?.mongo
			def databaseName = mongoConfig?.remove("databaseName") ?: grailsApplication.metadata.getApplicationName()
		  
			databaseName = databaseName?databaseName+'files':'files'
			DB db = mongo.mongo.getDB(databaseName)
	
			db.setWriteConcern(WriteConcern.SAFE)
			gridfs = new GridFS(db, bucket)
			_gridfs[bucket] = gridfs
		}
	
		return gridfs
	  }
	
	public String getMimeType(File file) {
		// use mime magic
		MagicMimeMimeDetector detector = new MagicMimeMimeDetector();
		Collection mimeTypes = detector.getMimeTypesFile(file);
		if (mimeTypes) return mimeTypes[0].toString()
	
		return "application/octet-stream"
	  }
	
	  public String getMimeType(byte[] ba) {
		// use mime magic
		MagicMimeMimeDetector detector = new MagicMimeMimeDetector();
		Collection mimeTypes = detector.getMimeTypesByteArray(ba);
		if (mimeTypes) return mimeTypes.iterator().getAt(0).toString()
	
		return "application/octet-stream"
	  }
	  
	  public void deliverGridFSFile(HttpServletResponse response, GridFSDBFile file, String filename = null, boolean asAttachment = true) {
		  response.setContentType file.getContentType()
		  response.setContentLength ((int)file.getLength())
		  if (filename == null) filename = file.getFilename()
		  if (asAttachment) response.setHeader("Content-Disposition", "attachment; filename=\"" + filename + "\"");
	  // response.setHeader("Cache-Control", "no-store");
	  // response.setHeader("Pragma", "no-cache");
	  // response.setDateHeader("Expires", 0);
	  
		  try {
			IOUtils.copy(file.getInputStream(), response.getOutputStream())
		  } catch (Exception e) {
			try {
			  // todo log
			  response.sendError(HttpServletResponse.SC_NOT_FOUND);
			} catch (IOException ignored) {}
		  }
		}
}